Generally, there is known a water content detection sensor for detecting presence or generation of water content or moisture at a time when the water content or water adheres between electrodes and electric current passes (Such water content detection sensors are disclosed, for example, in Patent Literature 1, 2, 3.). Such water content detection sensors are utilized for automatic wipers of automobiles, diapers and so on.    Patent Literature 1: JP-63-290950    Patent Literature 2: JP-2000-19136    Patent Literature 3: JP-2002-82080